Article Unintended Subdural Injection

Front 1

Vagal predominance is known to be an important factor in development of _______ during regional anesthesia

Back 1

bradycardia

Front 2

EXAM QUESTION

Bezold-Jarisch reflex has what 3 physiologic symptoms?

Back 2

Vasodilation
Hypotension
Bradycardia

Front 3

Bezold-Jarisch reflex is mediated via....

Back 3

afferent nerves from the heart and by noncardiac baroreceptors

Front 4

Bezold-Jarisch reflex is more profound in the face of ______?

Back 4

Hypovolemia

Front 5

Vasodilation from oral nitroglycerin can last how long?

Back 5

Up to 60 minutes

This further compounds the patient's ability to compensate.

Front 6

Motor block is how many dermatomes lower than sensory?

Back 6

2-4

Front 7

Sympathetic block is how many dermatomes above the sensory?

Back 7

2-6

Front 8

Sympathectomy provides the following physiological changes.

Back 8

Decreased blood pressure
Decreased return of blood to the heart (preload)
Increased heart rate

Front 9

Variable onset of an epidural and extension of neural blockade and occult creation of a subdural space under conditions of microscopic trauma during placement of a routine epidural anesthetic...lead to

Back 9

unintended subdural deposit of local anesthetic

Front 10

Splanchnic fibers are what dermatome levels?

Back 10

T6-L1

Front 11

If the splanchnic fibers are blocked what can happen?

Back 11

Significant pooling of the blood in the gut and abdominal viscera.

Front 12

EXAM QUESTION

How much of the total blood volume does the splanchnic blood reservoir contain?

Back 12

20-40%

Front 13

Normal sympathetic activity does what?

Back 13

increases resistance
decreases splanchnic blood volume
increases systemic blood volume
elevates systemic arterial pressure

Front 14

Venous capcitance vessels contain what percent of circulating blood volume?

Back 14

80%

Front 15

Venodilation in the lower extremities has potential for what dramatic physiologic changes?

Back 15

Decreased venous return
Reduced right atrial filling pressure
Reduced cardiac output

Increased vagal tone

Front 16

Thoracolumbar blockade (T10 and higher) can lead to a reduction in adrenal activity and subsequent.....?

Back 16

reduced secretions of available catecholamines.

Front 17

List 5 different rationale for "Patchy" blocks or asymmetrical blocks

Back 17

-nonuniform expansion of potential epidural space
-anatomic obstacles in the potential epidural space
-dilution of familiar medications
-catheter migration to one side
-partial subdural block with neuraxial conduction loss that does not fit the pattern of a predictable or intended subarachnoid/epirual anesthetic

Front 18

What is the incidence of an accidental subdural deposit of LA intended for epidural blockade

Back 18

0006% and 17%

Front 19

EXAM QUESTION

How do you recognize an unintended subdural injection?

Back 19

Extensive neural blockage that is out of proportion to the amount of local anesthetic injected
may be suspected in the absence of an identified subarachnoid puncture.

Front 20

The subdural space has a poor blood supply and therefore loss of effect of local anesthetic is dependent on...?

Back 20

diffusion away from the site.

Injected medium may stay in that space for a considerable time.

Front 21

The arachnoid layer is composed of

Back 21

large cells with numerous cellular junctions,
no extracellular space
no extracellular collagen

Front 22

The dural is composed of ________?

Back 22

Elongated, flattened fibroblasts
copious amounts of extracellular collagen

Front 23

Drual border cell layer is found at the dura-arachnoid junction and is composed of what?

Back 23

flattened fibroblasts
extracellular spaces
NO extracellular collagen and a few cell junctions

Front 24

What is the dura-arachnoid interface?

Back 24

space can appear as neurothelial cells break up because of pressure exerted by mechanical forces creating fissures within the amorphous substance of the interface.

Front 25

EXAM QUESTION

Unintended subarachnoid injection following epidural placement usually manifests as_____?

Back 25

Block that is bilateral with profound onset and even with lower doses of isobaric or hypobaric local anesthetic solution more intense than usually is seen following administration of drug into the epidural space.

Front 26

EXAM QUESTION

Subdural, nonintrathecal injection is suspected with what clinical picture?

Back 26

unilateral, uneven, or inadequate block with delayed onset and a disproportionate sympathectomy secondary to a higher than expected level.

Front 27

Involvement of a block at level of shoulder girdle and neck muscles would indicate a level obtained between what nerve roots?

Back 27

C5-T1

Front 28

The rhomboidus major and minor are responsible for scapular rotation and elevation (Shoulder shrug) and their innervation is shared between what nerve roots?

Back 28

C4-C5

Front 29

Phrenic nerve originates at what nerve roots?

Back 29

C3-C4-C5

Front 30

What nerves include the cardioaccelerator fibers?

Back 30

T1-T4